Immies and Aggies is an unreleased prototype for the Atari 2600.
Immies and Aggies is an odd shooting game that involves marbles. For you see, Immies and Aggies are actually types of marbles (Aggies are agates, while Immies are glass imitations of agates), although from the game graphics you really can't tell. In fact the graphics consist mostly of squares that appear to be randomly placed around the screen.
The goal of the game appears to be to shoot the proper colored marble (square) with your little blaster. On the top of the screen there is colored box that displays the current color, while several different shaped squares will appear in a random pattern in the middle of the screen. As the colored box slowly disappears, you must shoot as many squares matching the current color as you can. Many times there will not be any squares of the proper color, so you will have to wait a few seconds for more squares to appear. Once the colored box completely disappears, it will be replaced by a new color which you will have to match.